The TPS51020 is a multi-function dual-synchronous step-down controller for notebook system power. The part is specifically designed for high performance, high efficiency applications where the loss associated with a current sense resistor is unacceptable. The TPS51020 utilizes feed forward voltage mode control to attain high efficiency without sacrificing line response. Efficiency at light load conditions can be maintained high as well by incorporating autoskip operation. A selectable, Suspend to RAM (STR) supported, DDR option provides a one chip solution for all switching applications from 5-V/3.3-V supply to a complete DDR termination solution.